Concrete, mortar, asphalt, road base, well-drilling fluids and muds, and other construction materials often contain clays that are carried in the sand, rock, gravel, or other aggregates that are used for making these construction materials or that are often intermingled into these construction materials. Clays can adversely affect the properties and/or performance of construction materials because they absorb water and chemical agents used for treating these materials.
A method for mitigating the deleterious effects of clays is to wash the clay from the aggregates. However, excessive washing can remove a portion of fines (i.e., small aggregates) that otherwise benefits the performance or enhances a desired property of the construction material.
An objective of the present invention is to mitigate the deleterious effects of clays carried in aggregates while improving one or more properties of the construction materials. The present invention can lead to improvements in the properties of mortars and concretes (e.g., workability, strength), asphalts (e.g., binder demand), and road base materials (e.g., improved flowability). Reducing or eliminating washing steps can lead to greater beneficial fines content in construction materials.
Additional benefits can also be realized for clay stabilization in gas and oil well applications (involving fractured rock formations) to reduce water loss.